1. Department of Materials Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871, Japan, Institute of Fundamental Chemistry, Technical University of Szczecin, Al. Piastów 42, PL-71065 Szczecin, Poland, and Institut für Organische Chemie, der Ludwig-Maximilians-Universität, München, Karlstrasse 23, D-80333 München, Germany